igbvf_open - Called when a network interface is made active : network interface device structure

Returns 0 on success, negative value on failure

The open entry point is called when a network interface is made active by the system (IFF_UP). At this point all resources needed for transmit and receive operations are allocated, the interrupt handler is registered with the OS, the watchdog timer is started, and the stack is notified that the interface is ready.

The close entry point is called when an interface is de-activated by the OS. The hardware is still under the drivers control, but needs to be disabled. A global MAC reset is issued to stop the hardware, and all transmit and receive resources are freed.